JPH0322957Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a shield structure for high frequency equipment, and particularly to a mounting structure for a shield plate arranged substantially parallel to a printed circuit board.

Conventional technology In high-frequency equipment that processes high-frequency signals,
The shield function is important, and accurate placement is required when installing the shield plate used for this purpose. For example, in an electronic tuner, a shield plate is interposed to electromagnetically shield a portion of a wiring body housed in a chassis base frame from other portions. The shield plate is fitted onto and held by the printed circuit board of the wiring body and the chassis base frame, and fixed by soldering.

In such a shield structure, for example, as shown in FIGS. 3 and 4, a wiring body of a printed circuit board 2 is housed in a chassis base frame 1, and a peripheral grounding pattern 3 of the circuit board is connected to the chassis base frame 1. A shield plate 5 having an L-shaped cross section and electromechanically bonded with solder 4 is disposed between the base frame 1 and the central ground pattern 6 of the board. The shield plate 5 consists of a flat main part 5a and a bent part 5b, one end of which has a tongue piece 5c of the bent part 5b penetrating the printed circuit board 2 and connected to the central grounding pattern 6 with solder 4, and the other end. The ends are a pair of protrusions 1a of the frame 1,
1b and connected with solder 4. Prior to soldering, the shield plate 5 is attached to the frame 1 by inserting the tongue piece 5c into the through hole 2a of the printed circuit board 2.
It is fitted into the gap between the protrusions 1a and 1b and is temporarily held.

By the way, the above-mentioned soldering is generally performed by assembling the wiring components on the printed circuit board 2 on the frame 1, temporarily fixing the components using a jig, and then soldering them all at once using a solder dip method. Therefore, ease of assembly of each component and reliability of soldering are required.

Problems to be Solved by the Invention The important problem in the above-mentioned shield structure was the assembling work of the shield plate 5 and the position regulation until it was temporarily fixed and soldered. In other words, the temporary fixing of the shield plate 5 may be uncertain, or the shield plate 5 may be displaced and fall off before soldering. This is done after inserting the tongue piece 5c into the through hole 2a of the printed circuit board 2 in order to assemble the shield plate 5.
The shield plate 5 is deformed because it is inserted between the pair of locking portions 1a and 1b by pushing along the slope of one of the locking portions 1a with the end surface of the shield plate a in contact with the inner wall of the base frame 1. In particular, as the bending angle becomes smaller, the elastic contact of the tongue piece 5c decreases, which tends to cause misalignment during soldering.

Therefore, the present invention has been proposed in view of the above, and aims to provide a shield structure that is easy to assemble and maintains an accurate mounting position.

Means for Solving the Problems The present invention is to solder the peripheral side grounding pattern of the printed circuit board to the chassis base frame, and electrically connect the center side grounding pattern partially through a spaced shield plate. In this case, as a structure for attaching the shield plate to the chassis base frame, a protrusion is provided on the frame, a locking portion that engages with the protrusion is provided on the shield plate, and both are accurately soldered and fixed at a predetermined position. In particular, a shield structure is provided that is easy to assemble by forming the locking portion of the shield plate by cutting and raising it.

Embodiment The following is an embodiment of the present invention as shown in FIGS.
This will be explained in detail with reference to the figures.

In the figure, an electronic tuner 1 which is a high frequency device
0, a printed circuit board 12 is attached to a chassis base frame 11, and a shield plate 13 is horizontally arranged on a part of the printed circuit board 12. The shield plate 13 consists of a horizontal main portion 14 and a bent upright portion 15. The tip of the upright portion 15 has a tongue piece 16, and a through hole of the printed circuit board 12 is connected to the central ground pattern of the printed circuit board 12. inserted into. This tongue piece 16 is fixed by soldering in the same manner as in the conventional structure shown in FIG.

The present invention is that a cut-and-raised locking portion 17 is provided at the other end of the main portion 14 of the shield plate 13, and a protruding portion 18 is provided on the base frame 11 in correspondence with the locking portion 17. That is, one end of the shield plate 13 solders the tongue piece 16 to the ground pattern on the center side of the printed circuit board, while the other end engages the locking part 17 with the frame protrusion 18 for accurate positioning. be done. This positioning is effectively performed by the locking portion 17 which is made by cutting out the cut portion from the end face of the main portion 14 of the shield plate 13 and at the same time. Note that the protrusion 18 causes the frame 1 to partially protrude, and the two illustrated protrusions may be integrally formed embossments. In addition, a bulge 19 is formed on the frame 11 of the shield plate 13 to restrict the main portion 14 thereof upward. The assembled shield plate 13 is soldered by hand and electromechanically fixed.

Effects of the Invention According to the above configuration, since the shield plate itself is provided with a cut-and-raised locking portion and engaged with the frame protrusion, accurate and reliable placement can be achieved without any positional deviation during assembly work. In addition, preventing misalignment during assembly reduces the need for correction work in subsequent processes, which helps improve the efficiency of assembly work, which has great practical effects.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the main part of the shield structure according to the present invention, Fig. 2 is a sectional view of the main part along the line B-B in Fig. 1, and Fig. 3 is a perspective view showing a similar conventional shield structure. , and FIG. 4 are cross-sectional views taken along line A-A in FIG. 3. 11... Base frame, 12... Printed circuit board, 13... Shield plate, 14... Main part, 17
. . . Cut-and-raised locking portion, 18 . . . Frame protrusion.

Claims (1)

[Claims for Utility Model Registration] The peripheral ground pattern of the printed circuit board is electromechanically coupled to the chassis base frame, and a shield plate separate from the frame is provided between the center ground pattern of the board and the frame. In the shield structure arranged parallel to the board, a protruding part is provided inside the frame, a cut-and-raised locking part corresponding to the protruding part is provided at the end of the shield plate, and the shield plate is engaged with the protruding part of the frame. A shielding structure for high frequency equipment characterized by being fixed and soldered.